@import url('https://fonts.googleapis.com/css2?family=Atkinson+Hyperlegible:wght@400;700&display=swap');

/* ===== 基础重置 ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #000000;
  --bg-card: #121212;
  --bg-elevated: #1a1a2e;
  --accent-blue: #1e3a5f;
  --accent-mid: #2d5a8e;
  --accent-bright: #4a9eff;
  --accent-glow: #6fb3ff;
  --accent-gold: #c9a84c;
  --text-primary: #f0f0f0;
  --text-secondary: #a0a0b0;
  --text-muted: #606070;
  --border: #1e1e2e;
  --border-bright: #2d5a8e;
  --nav-h: 56px;
  --radius: 4px;
  --font: 'Atkinson Hyperlegible', 'Segoe UI', system-ui, -apple-system, sans-serif;
  --transition: 0.25s ease;
  color-scheme: dark;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}

body.dark-mode.oled-bg {
  background: #000000;
}

a {
  color: var(--accent-bright);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover, a:focus-visible {
  color: var(--accent-glow);
  text-shadow: 0 0 10px rgba(111, 179, 255, 0.5);
  outline: none;
}

a:focus-visible {
  outline: 2px solid var(--accent-bright);
  outline-offset: 2px;
}

ul, menu {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ===== 滚动边距（固定底导） ===== */
section[id] {
  scroll-margin-top: 72px;
}

/* ===== 站点容器 ===== */
.site-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ===== 英雄区 ===== */
.hero-wrap {
  position: relative;
  width: 100%;
  min-height: 100vh;
  display: flex;
  align-items: flex-end;
  justify-content: flex-end;
  padding: 0 5vw 12vh 5vw;
  overflow: hidden;
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  filter: brightness(0.35);
}

.hero-bg-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(0,0,0,0.85) 0%,
    rgba(10,20,40,0.7) 50%,
    rgba(0,0,0,0.9) 100%
  );
}

.hero-bg-wordmark {
  position: absolute;
  bottom: -0.15em;
  left: -0.05em;
  font-size: clamp(6rem, 20vw, 18rem);
  font-weight: 700;
  color: transparent;
  -webkit-text-stroke: 1px rgba(74, 158, 255, 0.08);
  text-stroke: 1px rgba(74, 158, 255, 0.08);
  letter-spacing: -0.04em;
  user-select: none;
  pointer-events: none;
  white-space: nowrap;
  line-height: 1;
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: right;
  max-width: 680px;
  padding-bottom: var(--nav-h);
}

.hero-eyebrow {
  font-size: 0.8rem;
  letter-spacing: 0.25em;
  color: var(--accent-bright);
  text-shadow: 0 0 10px rgba(74, 158, 255, 0.6);
  margin-bottom: 1rem;
  text-transform: uppercase;
}

.hero-h1 {
  font-size: clamp(2rem, 6vw, 4.5rem);
  font-weight: 700;
  line-height: 1.15;
  color: #ffffff;
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
  text-shadow: 0 0 40px rgba(74, 158, 255, 0.2);
}

.hero-desc {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  margin-bottom: 2rem;
  line-height: 1.65;
}

.hero-cta {
  display: inline-block;
  padding: 0.85rem 2.5rem;
  background: transparent;
  border: 1.5px solid var(--accent-bright);
  color: var(--accent-bright);
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  border-radius: var(--radius);
  transition: background var(--transition), color var(--transition), box-shadow var(--transition);
  cursor: pointer;
}

.hero-cta:hover, .hero-cta:focus-visible {
  background: var(--accent-bright);
  color: #000;
  box-shadow: 0 0 24px rgba(74, 158, 255, 0.4);
  text-shadow: none;
}

.hero-clip-bottom {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  background: var(--bg);
  clip-path: polygon(0 100%, 100% 40%, 100% 100%);
  z-index: 3;
}

/* ===== 主内容 ===== */
.site-main {
  flex: 1;
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 3rem 1.5rem 6rem;
}

/* ===== 内容 section（结构抽签：main > section > figure/aside 交错）===== */
.content-section {
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-rows: auto 1fr;
  gap: 2rem;
  position: relative;
}

.content-figure {
  grid-column: 1;
  grid-row: 1 / 3;
  width: 4px;
  align-self: stretch;
  margin: 0;
}

.figure-deco {
  display: flex;
  flex-direction: column;
  align-items: center;
  height: 100%;
  gap: 0;
}

.deco-line {
  flex: 1;
  width: 1px;
  background: linear-gradient(to bottom, transparent, var(--accent-mid), transparent);
}

.deco-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-bright);
  box-shadow: 0 0 10px var(--accent-glow);
  flex-shrink: 0;
  margin: 8px 0;
}

.content-aside {
  grid-column: 2;
  grid-row: 1;
  /* aside 在右侧由父 grid 实现 */
}

.content-body {
  grid-column: 2;
  grid-row: 2;
}

/* 桌面：aside 放右侧，body 占主区 */
@media (min-width: 900px) {
  .content-section {
    grid-template-columns: 4px 1fr 300px;
    grid-template-rows: auto;
    align-items: start;
  }

  .content-figure {
    grid-column: 1;
    grid-row: 1;
  }

  .content-body {
    grid-column: 2;
    grid-row: 1;
  }

  .content-aside {
    grid-column: 3;
    grid-row: 1;
    position: sticky;
    top: calc(var(--nav-h) + 1.5rem);
    align-self: start;
  }
}

/* ===== 正文内容样式 ===== */
.content-body h2 {
  font-size: clamp(1.4rem, 3vw, 2rem);
  color: #fff;
  margin: 2.5rem 0 0.5rem;
  line-height: 1.3;
}

.content-body h2 + hr,
.content-body h3 + hr {
  border: none;
  border-top: 1px solid var(--accent-mid);
  margin: 0.5rem 0 1.25rem;
}

.content-body h3 {
  font-size: clamp(1.1rem, 2.5vw, 1.5rem);
  color: var(--accent-bright);
  margin: 2rem 0 0.4rem;
  text-shadow: 0 0 10px rgba(74, 158, 255, 0.25);
}

.content-body p {
  font-size: 1.05rem;
  color: var(--text-primary);
  margin-bottom: 1.1rem;
  line-height: 1.75;
}

.content-body ul, .content-body ol {
  padding-left: 1.5rem;
  margin-bottom: 1.1rem;
}

.content-body li {
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

.content-body strong {
  color: #fff;
  font-weight: 700;
}

.content-body em {
  color: var(--accent-gold);
  font-style: normal;
}

.content-body blockquote {
  border-left: 3px solid var(--accent-bright);
  padding: 0.75rem 1.25rem;
  margin: 1.5rem 0;
  background: var(--bg-card);
  border-radius: 0 var(--radius) var(--radius) 0;
  color: var(--text-secondary);
}

.content-body section {
  margin-bottom: 3rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

.content-body section:last-child {
  border-bottom: none;
}

.content-body figure {
  margin: 1.5rem 0;
}

.content-body figure img {
  border-radius: var(--radius);
  width: 100%;
}

.content-body figcaption {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
  text-align: center;
}

/* ===== aside 侧栏 ===== */
.aside-inner {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-bottom: 3px solid var(--accent-bright);
  border-radius: var(--radius);
  padding: 1.5rem;
}

.aside-title {
  font-size: 0.85rem;
  letter-spacing: 0.15em;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-bottom: 0.4rem;
}

.aside-hr {
  border: none;
  border-top: 1px solid var(--border-bright);
  margin-bottom: 1rem;
}

.aside-nav-list li {
  border-bottom: 1px solid var(--border);
}

.aside-nav-list a {
  display: block;
  padding: 0.6rem 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
  transition: color var(--transition), padding-left var(--transition);
  min-height: 44px;
  display: flex;
  align-items: center;
}

.aside-nav-list a:hover,
.aside-nav-list a:focus-visible {
  color: var(--accent-bright);
  padding-left: 0.5rem;
  text-shadow: none;
}

.aside-brand-block {
  margin-top: 1.25rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
}

.aside-brand-name {
  display: block;
  font-size: 1rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 0.35rem;
}

.aside-brand-desc {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.55;
}

/* ===== 底部固定导航条 ===== */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 1000;
}

/* 主展示条 */
.bottom-bar-strip {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(0, 0, 0, 0.95);
  border-top: 1px solid var(--border-bright);
  height: var(--nav-h);
  padding: 0 1rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  gap: 0.5rem;
}

.bar-left, .bar-right {
  display: flex;
  gap: 0.25rem;
  flex: 1;
}

.bar-right {
  justify-content: flex-end;
}

.bar-link {
  font-size: 0.72rem;
  color: var(--text-secondary);
  padding: 0.5rem 0.4rem;
  min-height: 44px;
  display: flex;
  align-items: center;
  white-space: nowrap;
  letter-spacing: 0.02em;
  transition: color var(--transition);
  border-radius: var(--radius);
}

.bar-link:hover, .bar-link:focus-visible {
  color: var(--accent-bright);
  text-shadow: 0 0 8px rgba(74, 158, 255, 0.5);
}

.bar-brand {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 0.75rem;
  min-height: 44px;
}

.nav-brand-text {
  font-size: 0.95rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.05em;
  text-shadow: 0 0 10px rgba(74, 158, 255, 0.3);
}

.nav-logo-img {
  height: 32px;
  width: auto;
}

/* details/summary 展开菜单（结构抽签：details > summary + menu > li > a）*/
.nav-details {
  position: absolute;
  bottom: 100%;
  left: 0;
  right: 0;
}

.nav-details[open] .nav-summary .nav-menu-icon span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}
.nav-details[open] .nav-summary .nav-menu-icon span:nth-child(2) {
  opacity: 0;
}
.nav-details[open] .nav-summary .nav-menu-icon span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

.nav-summary {
  list-style: none;
  cursor: pointer;
  position: absolute;
  bottom: 0;
  right: 1rem;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.nav-summary::-webkit-details-marker { display: none; }

.nav-summary-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
}

.nav-brand-center {
  display: none;
}

.nav-menu-icon {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 22px;
}

.nav-menu-icon span {
  display: block;
  height: 1.5px;
  background: var(--text-secondary);
  transition: transform var(--transition), opacity var(--transition);
  border-radius: 1px;
}

.nav-menu {
  background: rgba(10, 10, 20, 0.98);
  border-top: 1px solid var(--border-bright);
  padding: 1.5rem 1.5rem 1rem;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.nav-menu-cols {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1rem;
}

.nav-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.nav-col li a {
  display: flex;
  align-items: center;
  padding: 0.55rem 0.75rem;
  min-height: 44px;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-radius: var(--radius);
  transition: color var(--transition), background var(--transition);
}

.nav-col li a:hover,
.nav-col li a:focus-visible {
  color: var(--accent-bright);
  background: rgba(74, 158, 255, 0.07);
  text-shadow: none;
}

.nav-search {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--border);
}

.nav-search-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  letter-spacing: 0.08em;
}

.nav-search-input {
  flex: 1;
  background: var(--bg-card);
  border: 1px solid var(--border-bright);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 0.9rem;
  padding: 0.55rem 0.85rem;
  min-height: 40px;
  outline: none;
  transition: border-color var(--transition);
}

.nav-search-input:focus {
  border-color: var(--accent-bright);
  box-shadow: 0 0 0 2px rgba(74, 158, 255, 0.15);
}

.nav-search-input::placeholder {
  color: var(--text-muted);
}

/* ===== 页脚（footer > section×n）===== */
.site-footer {
  background: var(--bg-card);
  border-top: 1px solid var(--border-bright);
  padding-bottom: calc(var(--nav-h) + 1rem);
}

.footer-brand-section {
  padding: 4rem 2rem 2.5rem;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.footer-brand-big {
  font-size: clamp(3rem, 10vw, 7rem);
  font-weight: 700;
  color: transparent;
  -webkit-text-stroke: 1px rgba(74, 158, 255, 0.3);
  text-stroke: 1px rgba(74, 158, 255, 0.3);
  letter-spacing: -0.03em;
  line-height: 1;
  margin-bottom: 1rem;
  user-select: none;
}

.footer-tagline {
  font-size: 0.95rem;
  color: var(--text-muted);
  max-width: 520px;
  margin: 0 auto;
  line-height: 1.65;
}

.footer-links-section {
  padding: 2.5rem 2rem;
  border-bottom: 1px solid var(--border);
}

.footer-links-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.footer-col-title {
  font-size: 0.8rem;
  letter-spacing: 0.15em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  text-transform: uppercase;
}

.footer-links-col hr {
  border: none;
  border-top: 1px solid var(--border-bright);
  margin-bottom: 1rem;
}

.footer-links-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.footer-links-col li a {
  font-size: 0.875rem;
  color: var(--text-secondary);
  padding: 0.3rem 0;
  display: block;
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: color var(--transition);
}

.footer-links-col li a:hover,
.footer-links-col li a:focus-visible {
  color: var(--accent-bright);
  text-shadow: none;
}

.footer-about-text,
.footer-keywords,
.footer-disclaimer {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 0.5rem;
}

.footer-bottom-section {
  padding: 1.5rem 2rem;
  text-align: center;
}

.footer-copy {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.footer-icp {
  font-size: 0.78rem;
  color: var(--text-muted);
  opacity: 0.7;
}

/* ===== hr 通用 ===== */
hr {
  border: none;
  border-top: 1px solid var(--border);
}

/* ===== 卡片样式（若正文用到）===== */
.card {
  background: var(--bg-card);
  border-radius: var(--radius);
  border-bottom: 3px solid var(--accent-bright);
  padding: 1.25rem 1.5rem;
  transition: transform var(--transition), box-shadow var(--transition);
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(74, 158, 255, 0.12);
}

/* ===== 动效：prefers-reduced-motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* ===== 响应式 ===== */
@media (max-width: 899px) {
  .content-section {
    grid-template-columns: 4px 1fr;
    grid-template-rows: auto auto;
  }

  .content-figure {
    grid-column: 1;
    grid-row: 1 / 3;
  }

  .content-aside {
    grid-column: 2;
    grid-row: 1;
  }

  .content-body {
    grid-column: 2;
    grid-row: 2;
  }

  .footer-links-cols {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .footer-brand-big {
    font-size: clamp(2.5rem, 15vw, 5rem);
  }
}

@media (max-width: 599px) {
  .site-main {
    padding: 2rem 1rem 5rem;
  }

  .hero-wrap {
    padding: 0 1.25rem 14vh 1.25rem;
    align-items: center;
    justify-content: center;
  }

  .hero-content {
    text-align: center;
    max-width: 100%;
  }

  .hero-h1 {
    font-size: clamp(1.75rem, 8vw, 2.5rem);
  }

  .hero-cta {
    display: block;
    width: 100%;
    text-align: center;
  }

  .bar-link {
    font-size: 0.62rem;
    padding: 0.4rem 0.25rem;
  }

  .nav-menu-cols {
    grid-template-columns: 1fr;
  }

  .footer-brand-section {
    padding: 2.5rem 1rem 1.5rem;
  }

  .footer-links-section {
    padding: 1.5rem 1rem;
  }

  .footer-bottom-section {
    padding: 1rem;
  }

  .content-section {
    grid-template-columns: 1fr;
  }

  .content-figure {
    display: none;
  }

  .content-aside {
    grid-column: 1;
    grid-row: 1;
  }

  .content-body {
    grid-column: 1;
    grid-row: 2;
  }
}

/* ===== 微动效 ===== */
@keyframes glowPulse {
  0%, 100% { text-shadow: 0 0 10px rgba(74, 158, 255, 0.4); }
  50% { text-shadow: 0 0 20px rgba(74, 158, 255, 0.8), 0 0 40px rgba(74, 158, 255, 0.3); }
}

.hero-eyebrow {
  animation: glowPulse 3s ease-in-out infinite;
}

@media (prefers-reduced-motion: reduce) {
  .hero-eyebrow {
    animation: none;
  }
}